


must be the chemistry between us

by fancyjeong



Category: TWICE (Band)
Genre: DUBCHAENG - Freeform, F/F, Fluff, confident gay dahyun because yes, panicked gay chaeyoung, soft, squint for jitzu, squint for sanayeon, the other members make an appearance, theyre all gay
Language: English
Status: Completed
Published: 2021-01-03
Updated: 2021-01-03
Packaged: 2021-03-13 12:49:31
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,587
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28528761
Author URL: https://archiveofourown.org/users/fancyjeong/pseuds/fancyjeong
Summary: chaeyoung should really be working on her late assignments and trying to pass her classes, but here she is, slipping another cringe-worthy chemistry pick up line into kim dahyun’s locker
Relationships: Kim Dahyun/Son Chaeyoung
Comments: 2
Kudos: 76





	must be the chemistry between us

**Author's Note:**

> how is this 3.5k words it was supposed to be short n cute.. anyways,, might write a second chapter for sanayeon and jitzu if i don’t get lazy lmao but hope u like this!! not proofread ignore any mistakes :]

chaeyoung really hates chemistry. everything about the subject irks her and makes her feel like punching a wall. she never really did understand why she had to know what ionic bonds were, or what good would knowing the whole periodic table do in real life. yet she’s stuck in chemistry class again, hearing the professor’s words but not processing them. 

she doodles on her book, among the diagrams of atoms and molecules. her eyes wander over to the girl sitting diagonally in front of her, and she feels her breath hitch. the familiar feeling of butterflies in her stomach return, and a warm spark starts somewhere in her chest — not that this hasn’t already happened about a hundred times before. 

kim dahyun always makes her feel like this. even when she’s doing absolutely nothing, just listening to the class, chaeyoung thinks she looks like the prettiest girl to walk to earth. an exaggeration, sure, but to chaeyoung she’s practically perfect. dahyun is everything good; she’s smart but she doesn’t shove it into people’s faces, she’s kind and is willing to help anyone in need (chaeyoung experienced this first-hand when her professor asked dahyun to tutor her a week before finals. the girl had been nothing but patient and understanding, and it was only thanks to her that chaeyoung scraped by with a grade of c afterwards.) 

dahyun is bright and always cheerful, she’s like sunshine on the best days, warm and welcoming. it certainly doesn’t hurt that she’s also very,  _ very _ pretty. chaeyoung swears she’s never met a more perfect person, despite tzuyu’s claims about jihyo already having that title. chaeyoung rolls her eyes when tzuyu tells her this, because of course she would say that — the girl is head over heels for the president of the school council. chaeyoung likes to tease tzuyu about how jihyo always seems to smile a little brighter whenever tzuyu is in the room, or how her cheeks colour red whenever tzuyu tells her she likes her outfit that day. 

sometimes chaeyoung likes dahyun so much it hurts. it hits her like a truck, leaves her feeling winded and weak. chaeyoung doesn’t think dahyun notices her much, not that it really matters. she doesn’t stand a chance with her, so she decides she’s content as long as she can see dahyun every chemistry class. 

chaeyoung convinces herself that it’s just a little crush, and that she’ll get over it soon enough. until sana convinces her to do something really, really dumb. and chaeyoung can’t believe she ever agreed to let sana talk her into doing this. 

/

and that’s how chaeyoung ends up standing in front of kim dahyun’s locker half an hour before the bell rings, slipping a piece of paper into her locker. 

she’s scrawled the message out in a handwriting that she hopes doesn’t resemble her own, and added a few doodles on the paper just so she doesn’t seem like a creep. 

_ are you copper and tellurium because you’re CuTe _

chaeyoung wants to slap herself. she can’t believe she wrote that with her own hands, and she can’t believe she’s actually done it. she turns back to where sana and tzuyu are watching her with shit-eating grins on their faces, cursing them under her breath. 

“i hate you. both of you.” chaeyoung grumbles, as her friends put their arms around her shoulders and ruffle her hair. 

“you’re too pussy to confess, we’re just helping you get a girlfriend!” sana says, and chaeyoung suddenly has a genius idea. 

“you’re talking like you have the guts to confess to nayeon,” chaeyoung retorts, “if i did this, you have to ask nayeon out, too.” 

sana tenses at this, her grin wiped off her face. “that’s stupid! just because you put a pick-up line in dahyun’s locker doesn’t mean i have to ask nayeon out too!” she whines, although she would really like for nayeon to go on a date with her. but she’s not even sure the older sees her like that. 

chaeyoung just shrugs, raising an eyebrow at sana. and sana really shouldn’t, but she can’t back down from a challenge, even if it’s one as stupid as this. “fine. i’ll ask nayeon out, but only if you continue putting lame pick-up lines in dahyun s locker for the rest of the week.” 

chaeyoung groans, but she figures,  _ it’s just for a week _ , and relents, much to sana’s excitement. tzuyu snickers at them, until sana loops her arm through hers and says, “how about you, tzuyu? if i ask nayeon out and chaeyoung continues this thing, will you finally ask jihyo out?” 

tzuyu’s cheeks flush, and the rational part of her tells her not to do it, especially since sana’s the one suggesting it — and bets with sana never end well. but she also really wants to go out with jihyo, and if she doesn’t take this opportunity she’s not sure when she’ll ever find the courage to ask her out again. and so tzuyu agrees, albeit a little hesitantly. 

/

on tuesday chaeyoung stands in front of dahyun’s locker again, wondering if dahyun received the one she sent yesterday. she wonders how dahyun had reacted to it, if she had even seen it. chaeyoung slips another piece of paper into her locker, looking around before leaving hurriedly. 

_ you must be made of uranium and iodine, because all i can see is U and I together <3 _

chaeyoung seriously wonders if anyone had ever actually tried to use these pick-up lines on someone they really liked in person. she thinks she would rather be hit by a bus than say any of these out loud. 

/

wednesday finds chaeyoung rushing to school, because she’s woken up later than usual and if she wants to make it in time, she’ll have to run. so she does. she sprints her way across the campus, praying dahyun hasn’t arrived at school yet. 

she heaves a sigh of relief when the hallway is still empty, apart from sana and tzuyu who meet her halfway there. chaeyoung rushes to take the piece of paper out from her pocket, and she feels kind of bad that it’s a little crumpled, but it’ll have to do. she pushes it through the tiny gap in dahyun’s locker and grabs her friends by their arms, urging them towards the cafeteria. 

_ are you sure we haven’t had a class together before? i could’ve sworn we had chemistry together... (no but we actually do have chemistry together lol) _

chaeyoung thinks revealing to dahyun that they have chemistry class together can’t be such a bad thing, after all, there were so many students in their class too. 

chaeyoung finds herself in a cafe near campus after classes, surrounded by textbooks and notes (most of them were sana’s, but chaeyoung doesn’t have the heart to tell her to move her stuff) 

she swears she feels her heartbeat quicken before she even looks up, because just hearing her voice makes chaeyoung all flustered. and in walks dahyun, textbooks in her arms balancing themselves despite her petite frame. chaeyoung should really stop staring, but she can’t help it. dahyun looks as gorgeous as ever, and so beautiful that chaeyoung could fall even harder than she already has. maybe she does. 

“hi chaeyoung! fancy seeing you here,” dahyun quickly catches sight of chaeyoung, and she’s snapped out of her staring. 

chaeyoung tries, she really does. she tries to speak up, to stop just staring at the floor beside dahyun’s shoes and to say hi back. but all she manages is a noise that sounds vaguely like a choked “hello” before sana kicks her under the table. 

“did you come here to study too?” dahyun asks, and chaeyoung thanks the gods that she pretends nothing happened. 

chaeyoung doesn’t think she has it in her to reply, not when dahyun is standing right next to her. not when she can smell dahyun’s perfume from where she sits; it smells like vanilla — cozy and refreshing. chaeyoung can’t open her mouth no matter how hard she tries, so she kicks sana back under the table, sending her a pleading gaze. 

her friend clears her throat, “ah, chaeyoung is a little sick right now and she has a sore throat, so she can’t really talk much.” she explains, and dahyun gives her a concerned look before nodding her head in understanding. 

“oh, i see. well, then i’ll see you tomorrow in class, chaeyoung! feel better soon, okay?” dahyun waves at her before walking towards a table not far away from where chaeyoung and sana are seated, joining a group of three other girls chaeyoung recognises as jeongyeon, momo and mina. chaeyoung barely manages a weak smile before she’s gone, and almost immediately sana starts teasing her about how she choked up in front of dahyun. 

chaeyoung rolls her eyes at sana, blocking out her words because she really doesn’t want to know how she looked and sounded like a dying fish, according to sana. then she overhears dahyun’s voice saying something that sounded a lot like, “they left another pick-up line today. they said we share the same chemistry class?” 

and chaeyoung tenses. sana stops her teasing, eyes wide as she, too, listens. 

“what if it’s some random creep who’s lying just to get into your pants? i honestly wouldn’t put it past any of the guys in our school, considering how they’re all horny half the time.” the girl whom chaeyoung  thinks  is jeongyeon says, with much disgust to her sentence. 

“good thing i’m gay, then.” dahyun laughs, and chaeyoung feels a tiny flutter of hope in her heart. in the short time they had spent together (read: the tutoring sessions that only lasted a week). dahyun had never mentioned anything about her sexuality, even when chaeyoung had accidentally let it slip that she was into women. and chaeyoung didn’t think it really mattered, anyways. but at least now she can say she hasn’t fallen for the straight girl, and in her books that was an accomplishment. chaeyoung couldn’t count the number of girls she had liked that had turned out to be straight even if she tried. 

“you do realise that all of us here are gay too, right?” momo says pointedly.

“anyways, i don’t think it’s a creepy guy. they seem genuinely nice, and it’s kinda cute, don’t you think?” dahyun asks as her friends stare at her. 

“still seems kinda fishy to me.” mina breaks the silence, and jeongyeon and momo agree with her almost instantly. 

“well, i guess we’ll just have to wait and see if they decide to reveal who they are.” dahyun says in finality, and chaeyoung feels a slight tug in her chest at how dahyun thinks the pick-up lines are cute. 

_dahyun thinks her pick up lines are cute..._ chaeyoung can’t help but smile at this. 

/

thursday morning chaeyoung pushes another slip of paper through dahyun’s locker before heading to classes. she’s not really sure what’s the point of her doing this, since she doesn’t stand a chance with dahyun at all. but if doing this means sana will finally ask nayeon out, and that tzuyu and jihyo will finally get together, she thinks it’s worth it. even if she won’t get a girlfriend out of this, (kim dahyun, in particular), at least her friends will. 

chaeyoung spends half of chemistry class doodling again, and the other half staring at the back of dahyun’s head. 

sometimes chaeyoung thinks she likes dahyun so much it hurts, right in her chest. it strikes her so suddenly at times; she could catch a glimpse of dahyun laughing at something one of her friends said, and chaeyoung could fall just as easily as she had the first time. it makes her feel giddy, her mind clouded and sometimes she feels like she can hardly breathe just looking at dahyun. the dull ache thumps just a little stronger every time she realises she’ll never get to love dahyun the way she wishes she could. 

and dahyun is everything nice; she reminds chaeyoung of autumn leaves and mornings with warm cups of coffees. she feels like the breeze of fresh air, and quiet afternoons in a cafe. 

dahyun feels like all of chaeyoung’s favourite things, yet she also reminds chaeyoung of the most bittersweet moments, ones where it hurts to look her in the eye, ones where chaeyoung tells herself to forget dahyun and move on, but she never really wants to. 

and chaeyoung thinks maybe she likes dahyun a little too much.

/

friday morning chaeyoung heads to dahyun’s locker again. sana and tzuyu were both busy with studying for their classes, so she’s left alone today. chaeyoung scrolls through her twitter on the way to dahyun’s locker, laughing to herself at the stupid tweets on her timeline (most of them were sana’s, and more than half of them were something along the lines of ‘i want a girlfriend’). chaeyoung snickers at this, because if she maybe just asked nayeon out, she would’ve had a girlfriend ages ago. but no, sana was always talking about how nayeon doesn’t like her  like that , or how nayeon probably likes jeongyeon. chaeyoung never knew sana could be this dense — it was painfully obvious that nayeon liked sana too, yet sana seemed to be the only one who didn’t notice. 

chaeyoung stops in front of dahyun’s locker, putting her phone away. until she realises she’s looking at a pair of shoes, right in front of dahyun’s locker. and those shoes look kind of familiar. 

“good morning, chaeyoung!” a cheery voice greets her, and chaeyoung thinks she could faint. 

“g-good morning d-dahyun!” she stumbles over her words, cheeks burning. the familiar feeling of momentary breathlessness hits her again, as it does every time she’s near dahyun. something seems to tighten in her chest, squeezing the life out of her heart for a short second and she’s left feeling as if she’s in a dream. everything suddenly feels surreal, like she’s not in control of her body. she can’t seem to feel anything anywhere, apart from where the knot in her stomach gets tighter, forcing her to take a deep breath. and even when she does, it doesn’t feel like it. she feels as if she’s watching everything unfold in third-person, and time seems to slow infinitely.

the moment drags on, until dahyun breaks the silence, “do you usually come to school this early?” 

and chaeyoung can’t answer. she stutters, “n-not really?” 

chaeyoung’s mind goes into overdrive, running a thousand miles an hour, because  _ what if dahyun asks her what she’s doing here? chaeyoung’s locker is in the other hallway; she wouldn’t have any reason to be here. and what if dahyun knows it’s her? should she just admit it? should she lie to dahyun and say that it’s just a stupid dare one of her friends made her do? why was dahyun even in school this early? and how was she going to put the piece of paper in her pocket into dahyun’s locker when she’s already here? _

chaeyoung’s breath quickens, coming in soft, shallow breaths. she has to get out of here. being around dahyun is suffocating when she already likes her this much, and even more so when she knows dahyun doesn’t return her feelings. it closes up on her, and she feels dizzy, light-headed. 

“i-i’m sorry, i have to go.” chaeyoung manages to say, before she starts to scurry past dahyun. 

“wait, chaeyoung!” dahyun’s hand catches her wrist. chaeyoung thinks this is it. she’s going to faint right here, in front of the girl she’s had a crush on for the past eight months. 

and fuck, does chaeyoung wish she  _ did  _ faint. it would be embarrassing, but not as embarrassing as having to answer dahyun’s next words. 

“did you not have another pick up line today?” 

chaeyoung pauses. because  _what the fuck is she supposed to say?_ chaeyoung thinks she should make a run for it right now. she should ignore dahyun’s hand (which was so,  so  soft) and leave. and maybe never show her face in this school again. but something in her pulls her down, like she can’t lift her feet. and she’s forced to look at dahyun, who stares back at her. chaeyoung isn’t sure what she sees in dahyun’s eyes. it doesn’t look anything close to disgust, or horror, or anything bad for that matter. 

“i didn’t mean to, but i saw you yesterday morning.” dahyun speaks again. “did you come here to put another one in my locker, by any chance..?” 

chaeyoung can’t run, not anymore. 

“not anymore, i guess...” she sighs softly, a look of defeat across her face. there wasn’t any point denying it now, seeing as dahyun had seen her with her own eyes. 

“why not?” dahyun says, sounding almost offended. 

“well, there’s no point now, really.” 

“you can give it to me now. you know, instead of putting it in my locker.” dahyun grins, holding out her hand. chaeyoung stares at it for a moment, before she reaches into her pocket and gently places it on dahyun’s outstretched palm. the older’s eyes flit across the words, her grin only growing wider. 

_ i wish i was adenine so i could get paired with U :] _

chaeyoung’s face burns red with embarrassment, and she wishes she could disappear in this moment. 

“thank you for these. they really make my day, you know?” dahyun looks up, smile so wide chaeyoung has to swallow down the words she wants to say so bad. 

“you don’t think they’re stupid?” 

“i think they’re really cute,” dahyun answers, “kinda like you, don’t you think?” 

chaeyoung visibly freaks out, sputtering for words. dahyun,  _the_ kim dahyun,  the girl she’s been crushing on for the past eight months, calling her  _cute_?  chaeyoung nearly slaps herself to make sure she’s not dreaming.

“y-you think i’m c-cute?” chaeyoung curses at how her voice shakes, at how stupid she sounds. 

“of course i think you’re cute!” dahyun giggles, and chaeyoung thinks she falls in love a little more. “that’s probably a biased opinion though, seeing as i’ve liked you for a while now.” 

oh, god. chaeyoung might really faint now. she feels the ground start to spin, feels like she can’t breathe anymore. dahyun’s hand on her wrist tightens as she sways a little, eyes unfocused. 

“are you alright?” dahyun is holding both her hands in hers now, and chaeyoung thinks if she were to faint she’d be happy as long as dahyun keeps holding her hands like this. 

“‘m alright...” she mumbles, as dahyun guides her to lean against the row of lockers, her face written sick with worry. “just... can you repeat that?” she whispers. 

“what, that i’ve liked you for quite a while now?” another wave of dizziness washes over chaeyoung as dahyun chuckles. 

“yeah, that.” chaeyoung laughs weakly, her feet feeling like they can’t support her body anymore. she didn’t have to worry much about that though, because she had somehow gone from leaning against the lockers to being held up by dahyun, and they were so very close now. “just trying to process that  _ the  _ kim dahyun likes me back. unless this is a prank. is this a prank?” chaeyoung pulls away suddenly, eyebrows furrowing. 

“no, silly. there’s no prank, just a confession i’ve been meaning to say for the past few weeks.” dahyun laughs again, light and cheerful and sounding like everything about dahyun that chaeyoung has fallen in love with. 

“why didn’t you?” 

“i wasn’t sure if you liked me like that,” 

“i was a stuttering mess every time we spoke! was that not enough of an indication that i liked you?” chaeyoung huffs, pouting. she’s not mad. no, she could never be mad at dahyun. she just thinks it’s rather stupid that she could’ve saved herself a lot of time pining after dahyun. 

“i don’t know! i thought maybe you were just bad at social interactions!” dahyun claims, earning a soft slap to her shoulder. 

“fuck, you’re telling me i could’ve had a girlfriend this whole time?” 

dahyun grins, “does that mean i’m your girlfriend now?” 

chaeyoung flushes, and the nerves return even though dahyun is looking at her like she’s the greatest person in the world. 

“would you want to be? my girlfriend, that is.” 

“i’ve never wanted anything more.” dahyun smiles softly, and chaeyoung is suddenly aware of the small distance between them. 

“then i’ll be yours.” chaeyoung whispers, as she presses a soft kiss on dahyun’s forehead. it feels like warmth, and happiness, and chaeyoung doesn’t really know why, but it feels like the colour yellow. a soft, pastel shade of yellow. perhaps it is because chaeyoung’s always loved the colour yellow, or maybe it’s because she associates yellow with happiness. chaeyoung decides it doesn’t matter why she feels the way she does, it only matters that she’s barely inches away from dahyun, who’s smiling at her like she’s the only person who matters. dahyun looks at her like she holds everything in her eyes, tender and loving. chaeyoung wishes she could tell dahyun how it feels to love her. how beautiful it is to like her; it feels like flowery petals falling gently onto her shoulders, feels like spring and autumn all at once. it’s the best thing she’s ever known. 

dahyun gently presses a kiss to the corner of her lips. she smiles softly, running her thumb over the back of chaeyoung’s hand. 

chaeyoung falls just a little more into everything of dahyun.

**Author's Note:**

> @nynluvr on twt!


End file.
